Stochastic block allocation for improved wear leveling

Abstract

Systems and methods are disclosed for stochastic block allocation for improved wear leveling for a system having non-volatile memory (“NVM”). The system can probabilistically allocate a block or super block for wear leveling based on statistics associated with the block or super block. In some embodiments, the system can select a set of blocks or super blocks based on a pre-determined threshold of a number of cycles (e.g., erase cycles and / or write cycles). The block or super block can then be selected from the set of super blocks. In other embodiments, the system can use a fully stochastic approach by selecting a block or super block based on a biased random variable. The biased random variable may be generated based in part on the number of cycles associated with each block or super block of the NVM.

Description

BACKGROUND OF THE DISCLOSURE [0001]NAND flash memory, as well as other types of non-volatile memories (“NVMs”), are commonly used for mass storage. For example, consumer electronics such as portable media players often include flash memory to store music, videos, and other media.[0002]A NVM can include multiple blocks and / or super blocks. In order to extend the lifespan of a NVM, it is preferable to have similar wear on all of the super blocks of a NVM. Therefore, in some cases, electronic devices may perform an operation known as “wear leveling” on one or more super blocks of the NVM.[0003]In order to determine which super block to select for wear leveling, a system may rely on statistics associated with each super block of the NVM. These statistics may indicate the number of times a particular super block has been erased or programmed, and are generally aggregated for a period of time before being recorded on the NVM.[0004]When a system experiences a power loss, however, unrecorde...

AI Technical Summary

Benefits of technology

[0005]Systems and methods are disclosed for stochastic block allocation for improved wear leveling. As used herein, “stochastic” block allocation can

Problems solved by technology

When a system experiences a power loss, however, unrecorded statistics may become lost.

As a result, the system may be unable to accurately determine which block to select for wear leveling purposes.

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